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# Test: Permanent Magnet DC (PMDC) Motors

## 10 Questions MCQ Test Electrical Machines | Test: Permanent Magnet DC (PMDC) Motors

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This mock test of Test: Permanent Magnet DC (PMDC) Motors for Electrical Engineering (EE) helps you for every Electrical Engineering (EE) entrance exam. This contains 10 Multiple Choice Questions for Electrical Engineering (EE) Test: Permanent Magnet DC (PMDC) Motors (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Permanent Magnet DC (PMDC) Motors quiz give you a good mix of easy questions and tough questions. Electrical Engineering (EE) students definitely take this Test: Permanent Magnet DC (PMDC) Motors exercise for a better result in the exam. You can find other Test: Permanent Magnet DC (PMDC) Motors extra questions, long questions & short questions for Electrical Engineering (EE) on EduRev as well by searching above.
QUESTION: 1

### The qualities aspired to obtain a good permanent magnet is/are

Solution:

Its both high residual flux as well as coercivity is desired for a good permanent magnet.

QUESTION: 2

### The type of field winding required in PMMDC is

Solution:

There is no field winding used in PMMDC to create the flux.

QUESTION: 3

### PMMDC are smaller in size due to

Solution:

There is no field winding used in PMMDC to create the flux. So it is lighter.

QUESTION: 4

PMMDC offers ______ characteristics.

Solution:

As the field remains constant due to the constant field, it has shunt characteristic.

QUESTION: 5

Select the possible dc magnetization characteristics of permanent magnetic materials.

Solution:

The magnetic field has a positive value when the magnetic field intensity, H has negative value due to coercivity property. We use second quadrant of hysteresis loop.

QUESTION: 6

Mark the speed torque characteristic of the PMDC.

Solution:

It is linear in nature and also analogous to shunt machine.

QUESTION: 7

PMDC had no ________ excited machine.

Solution:

It has no electrical excitation.

QUESTION: 8

How to manage run-away issue for dc shunt motor in industry?

Solution:

A PMDC motor can be used to replace the dc shunt motor in industries as they have quite identical characteristics.

QUESTION: 9

A PMMDC motor has as armature resistance of 4.2 ohms. When 6 V supply is applied to motor it runs at 1215 rpm drawing 14.5 mA on no-load. The rotational losses is

Solution:

Rotational losses = E*Ia = 5.939* 14.5/1000 = 86.1 mW.

QUESTION: 10

PMMDC can only be armature controlled.

Solution:

Due to absence of the field winding there is no option of field control.